Who am I²? MY name is U_def. Holistic Reason(s) and semantics

This article-testimony can be seen as an example of a maybe new discipline that could be called "scientific metaphysics" made of thoughts experiments, definitions, some proofs, some explanations, some conjectures. Of course, to be called science, the discipline needs some possibility of "verification" too. We will see if it can be considered. We start from a thought experiment: Can the universe defined as U_Def be aware conscious of itself as whole? This question is a variant of the more familiar: Can the universe be aware conscious? We can distinguish two main approaches in human history in the attempts at answering this second question: 1) the approach by the bottom with a weak version of consciousness: it includes "panpsychic" like theories. 2) the approach by the head with a strong version of consciousness: it includes "holistic" theories. Spinoza's "Pantheism", for example, can be considered as one of them, even if some interpretations of Spinoza's metaphysics are not satisfied with the equation "god = universe". The purpose developed in this article belongs to the second kind of approach. After a definition of the universe \emph{U}$_{\textit{Def}} $ in 7 points and the introduction of 3 premisses, one of them being devoted to our definition of "strong consciousness", we suggest an answer to the initial question and we draw the most important among numerous consequences: - semantical jump by META-abstraction and introduction of the holistic semantics; - extension of the natural language to a supra-natural language; - highlighting of a higher-order solipsism; - etc. We devote some attention to the notion of "model" in its logical and philosophical acceptation and we introduce the notion of evolutional self-modelization.